I believe him partly. Playing possum in combat sports isn’t unusual. Rope and Dope is a decent example. In MMA, Tim Elliot vs MM, recall Elliot pretending a body shot hurt more than it did, then opened up briefly when MM went to capitalize.
That said, if Cutelaba was acting drastically more rocked and dazed that moment than he was, I don’t entirely blame the ref for wanting to protect him. Yet fighters have recovered from worse situations. Depends how ya look at it, personally think he could have certainly let it go longer.